Polyurethanes and polyurethane/polyureas are widely employed as high performance engineering materials in a variety of industrial applications; the mechanical and physical properties for which they are considered the materials of choice in such applications are often directly relatable to the block-copolymer nature of these materials. The polyurethanes and polyurethane/polyureas are composed of blocks or segments of chemically different units. At service temperatures, one of the segments is generally viscous or rubbery ("soft" segment) while the other is of a glassy or semicrystalline nature ("hard" segment). Due to incompatabilities between the "hard" and "soft" components, these materials may undergo phase-separation in the solid-state resulting in the formation of a "soft" and "hard" two-phase microstructure. This phase separation observed in polymer systems leads to enhanced mechanical properties, such as tensile and modulus. In addition, the properties, service temperature limits, and utilities of such materials may often be improved or extended in industrial applications by crosslinking the polymer either thermally (with or without thermal initiator additives) or via ultraviolet light, gamma or accelerated electron beam radiation.
U.S. Pat. No. 4,366,301 describes the use of the acrylic or methacrylic acid ester of a trihydric alcohol, preferably the known compound 2,3-dihydroxypropyl acrylate (also called 1-glyceryl acrylate), as the unsaturated diol for crosslinking thermoplastic polyurethane resins containing ethylenic side groups.
U.S. Pat. No. 4,408,020 describes polyurethanes prepared from hydroxyl terminated polymers, organic diisocyanates and polyethers having terminal hydroxyl and unsaturated groups or terminal hydroxyl and pendent unsaturated groups. These polyurethanes are electron beam cured to form useful binder systems for magnetic tape.
U.S. Pat. No. 4,446,286 describes improved electron beam curable polyurethane compounds obtained from a mixture of (1) polyurethanes prepared from polymeric polyols, organic diisocyanates and polyethers having terminal hydroxyl and unsaturated groups or terminal hydroxyl and pendent unsaturated groups and (2) acrylate or alkacrylate terminated polyurethanes prepared by reacting isocyanate terminated prepolymers of hydroxyl terminated polymers with hydroxyl terminated acrylates or alkylacrylates.
U.S. Pat. No. 4,467,078 describes improved electron beam curable polyurethane compounds having a greater range in degree of cure, consequently providing systems with a greater range of hardness (modulus) for use in binder systems for magnetic tape.
A Russian publication (Chem.Absts.No. CA90(14):104388) Vysokomol. Soedin., Ser. B, 20(10),777-9 by Ezrielev and Arbuzova, describes linear polymers of glycerol monomethacrylate(PMMG) obtained from isopropylideneglyceryl methacrylate. The ketonic protection was removed from the monomer units by either acid hydrolysis, or preferentially, by alcoholysis and the resultant polymer was used to prepare hydrogels. Ezrielev and Arbuzova did not teach or suggest the use of 2-glyceryl methacrylate monomer.
The preparation of readily solvolyzable, polymerizable acrylate and methacrylate monomers and polymers is described in U.S. Pat. No. 4,578,504. One of the classes of monomers disclosed is represented by the formula: ##STR1## wherein R is hydrogen or methyl
X is fluoro, chloro, bromo, iodo, hydroxyl, perfluoroalkylsulfonoxy of one to three carbon atoms or perfluoroacyloxy of one to three carbon atoms, benzoyloxy, and trichloroacetoxy;
Y is trichloroacetyl, perfluoroacyl of the formula ##STR2## trialkylsilyl of the formula EQU [Ch.sub.3 (CH.sub.2).sub.m ].sub.3 Si-,
or hydrogen. The monomer wherein X and/or -OY is hydroxy is obtained by hydrolysis of compounds wherein X is perfluoroalkylsulfonoxy, perhaloacyloxy, benzoyloxy, or trialkylsiloxy.